The company says former U.S. Treasury Secretary Timothy F. Geithner made a 'threatening' phone call to its chairman after S&P's downgrade of U.S. debt in 2011.

McGraw Hill Financial Inc.'s Standard & Poor's unit may be allowed to seek information from former U.S. Treasury Secretary Timothy F. Geithner related to what the company said was a "threatening" call he made to McGraw Hill Chairman Harold W. McGraw III after S&P's downgrade of U.S. debt in 2011.

At a hearing Tuesday in Santa Ana, U.S. District Judge David Carter said he's concerned about why Geithner would have made the call to McGraw Hill's chairman three days after the downgrade, other than for it to have a "chilling effect."

"Why is Geithner calling?" Carter asked. "What is he doing on the phone?"

The judge didn't issue a final ruling on S&P's request before taking a recess.

S&P is seeking information from Geithner to argue that it was singled out because of the downgrade. It contends that the Justice Department retaliated last year with a fraud lawsuit accusing the company of lying about its ratings being free of conflicts of interest.

The Justice Department has said it may seek as much as $5 billion in penalties for losses to federally insured financial institutions that relied on New York-based S&P's ratings before the collapse of the U.S. housing market that wiped out the value of many of the securities.

McGraw said in a January court filing that Geithner called after the downgrade to inform him that "S&P's conduct would be looked at very carefully" and would be met with a response by the government. Geithner made the "angry" call right after he met with President Obama, according to S&P.

The U.S. has said the downgrade was based on a $2-trillion error by S&P and has denied any connection between the downgrade and its investigation of S&P, which it said started two years before the downgrade.